. >> you may recognize garrett peck from a former bookie did on probation in washington, d.c. is back at local history with a new book on the potomac river, a history and guide. what does the potomac river start and end of? >> it is near davis west virginia, a tiny little trickle that comes out of the side of the mountain and then it ends at point a look at which is 11 miles wide. the river is pretty wide at the mouth in between there's a huge amount of history. hundreds of historic sites. this is where our nation grew up on. it also has to nation's capital on it spent when we think about washington, d.c. we think about the national monument and the white house. and people think about the potomac river. why is it? >> when people think about washington, d.c. they think about -- why is that? >> certain people think about the potomac river, that's one of the things i was going to push towards, especially for people who live in the washington area, the potomac as interesting as an obstacle during the commute to work everyday because they're driving over it or going under it on the